Ice could act as bridge for Isle Royale wolves

January 31, 2014

HOUGHTON - On Isle Royale National Park, Lake Superior ice cover could also have consequences for the island's wolves, according to researchers with the island's famous wolf-moose study, which has been tracking those species' populations on the island since 1959.

"There's ice out there and it's certainly possible that animals could go back and forth," said Carolyn Peterson, a point person for the study in Houghton while researchers are on the island doing their annual count.

There were only 10 wolves living on the island as of last winter's count, many of them inbred and with poor genetic makeup. The packs are in danger of dying off and scientists, policy makers and the public have all been debating whether or not to import wolves to maintain the ecosystem's balance.

But an ice bridge to Canada, which is already in place, could allow new blood to cross to the island naturally. That's how wolves first got to the island in the late 1940s, and that's how a single male know as Old Grey Guy drastically improved island packs' genetics when it migrated from Canada in 1997.

"When these wolves don't perceive a local opportunity to mate, they consider going for a walk - a long walk - to find other opportunities," study leader John Vucetich wrote recently in an update on the study's web site, isleroyalewolf.org.

But it's perhaps more likely, according to Peterson, that wolves will migrate off the island to Canada, as researchers believe happened when two radio-collared wolves disappeared in 2008, the last time an ice bridge formed.